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Date: Thu, 8 Apr 2004 19:42:05 +0200
From: Radim Kolar <hsn@netmag.cz>
To: freebsd-fs@freebsd.org
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Subject: maximum size of cylinder group superblock supported by kernel
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Hi,

 I have started to write inode booster program. It should add new free inodes
 to filesystem without enlarging it. I am running out of inodes on many
 computers. 
 
 I have found that newfs creates filesystem with cylinder group block (struct
 cg from fs.h) maxed to filesystem's blocksize. In my case there are only 4
 free bytes, so there is no much space for increasing iused bitmap. I have read
 in several source code comments about `bsd can not handle larger struct cg
 than blocksize`. 

 Can anybody fix kernel to support larger struct cg ? Why is hard to support
 any sized struct cg ? Real size is recorded in superblock.fs_csgsize field,
 so kernel can look in sb and load as much data as needed.

 Anybody have some idea what should i do with my code? I have created classes
 for manipulating UFS2 ondisk. I can can do easily for example inodes ->
 datablocks space conversion, but this is not very usefull.